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What is the difference between is_a and instanceof?
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Update
As of PHP 5.3.9, the functionality of is_a() has changed. The original answer below states that is_a() must accept an Object as the first argument, but PHP versions >= 5.3.9 now accept an optional third boolean argument $allow_string (defaults to false)...
Find difference between timestamps in seconds in PostgreSQL
I have a table in PostgreSQL 8.3 with 2 timestamp columns. I would like to get the difference between these timestamps in seconds. Could you please help me how to get this done?
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Sending command line arguments to npm script
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Edit 2014.10.30: It's possible to pass args to npm run as of npm 2.0.0
The syntax is as follows:
npm run <command> [-- <args>]
Note the necessary --. It is needed to separate the params passed to npm command itse...
What is the use of the @ symbol in PHP?
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It suppresses error messages — see Error Control Operators in the PHP manual.
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Draw in Canvas by finger, Android
...ngerpaint demo in the sdk sample.
Another Sample:
public class MainActivity extends Activity {
DrawingView dv ;
private Paint mPaint;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
dv = new DrawingView(this)...
Downloading a file from spring controllers
I have a requirement where I need to download a PDF from the website. The PDF needs to be generated within the code, which I thought would be a combination of freemarker and a PDF generation framework like iText. Any better way?
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Fastest way to check if a string matches a regexp in ruby?
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Starting with Ruby 2.4.0, you may use RegExp#match?:
pattern.match?(string)
Regexp#match? is explicitly listed as a performance enhancement in the release notes for 2.4.0, as it avoids object allocations performed by other methods s...
Running Python code in Vim
I am writing Python code using Vim, and every time I want to run my code, I type this inside Vim:
20 Answers
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What is attr_accessor in Ruby?
... two different methods. The former is called reader and latter is called writer. We didn't create the writer yet so let's do that.
class Person
def name
@name
end
def name=(str)
@name = str
end
end
person = Person.new
person.name = 'Dennis'
person.name # => "Dennis"
Awesome. ...
How to get an enum value from a string value in Java?
...n source code. They do appear in Javadoc, though; for example, Dialog.ModalityType shows both methods.
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